Renewable electric fuse



R. G. SANDS RNEWABLE ELECTRIC FUSE n Nov. 13, 1923.

Filed June` 3, 1920 VTo @ZZ 'wlw/m t may concern.'

Patented Nov. 13, 1923.

UNITED STATES PATENT 'ori-fics.

noY e. SANDS, or wAUKEGAN, ILLINOIS, assienoa rfro CooirnLnC'raIC CCMPANY, v

or CHICAGO, ILLINoIs, a conformaron or fILLINoIs.

Y RENEWABLE nrino'rnio rosa..

Application flied June a, 192e. sensi N6. 386,208.

Be it known that l, Rox GRANVILLE SANDS, a citizen oi' tlielUnited States, residing at i/Vaulegan, in the county of Lake and State of Illinois, have invented new and useful improvements in Renewable Electric Fuses, ot' which the following is a full, clear,

concise, and exact description, reference being had to the accompanying drawing, forming a part of this specification.

My invention relates to electric 'fuses and it has special reference to that type ot electric fuses known as renewable fuses.

More particularly my invention pertains to a fuse of the type indicated above which embodies means for insuring, under all conditions ot' operations, complete electrical contact between a renewable fusible linlrand the permanent members associated therewit which comprise the fuse. 6

An object of my invention is to provide a renewable iuse of the character designated which may be readily assembled and which embodies a fusible element that may be conveniently replaced without requiring any new parts or members, with the exception of the fusible element.

Another object of my invention is to provide a fuse which willy Abe economical to construct and which embodies in its structure very few permanent parts, none of which is subject to rapid deteriorationor requires replacement when the fusible element is being renewed.

For a better understanding of my invention, reference may be had to the following description and the accompanying drawings, in which: Y Y Fig. 1 represents a side view of an elec tric fuse, partlyassembled, that is constructed in accordance with my invention;

. Fig.` 2 is a view, partially in elevation and partially in section, oit the upper portion oi the fuse o'jFig. l; Y

Fig. 3 is a plan view taken 'along the sectional line 3 3 of Fig. 2;

Figf 4 is a perspective view'showing one of the washers that comprises a permanent `member of my renewable electric fuse;

Fig. 5 is a view inperspective of a fusible 'elementthat may be embodied injthe renewable electric fuses fof my present inven-V tion; Y

Fig. Gis a side view of a modified form of Vmy invention;

F ig. 7 is a view, partially in elevation and partially in section, oit the fuse illustrated in Fie" 6* Fig. 8 is a plan view of the electric fuse I illustrated in liig. y7; and

-fifig 9 is a perspective view'oiI the washer incorporated in the Velectric fuse illustrated in Figs. G, Z and 8. y

Attention is` first 'directed to the renewable electric inse illustrated in Figs. l to 5 inclusive wherein l'the tubular casing 1i, made orn electrical insulating material, such as libre, is adapted to be provided at both of its ends with metallic VAcaps or lerrules 2, only one being shown. ifiupported by each of the caps 2 is an electrical terminal member 3 which, in this instance, comprises a fia-t portion 4 having an integrally formed and rip-standthe insulating tubular shell 1V are exteriorly threaded in the manner indicated at 6. The

metallic caps 2 are interiorly threaded so as to engage the screw threads 5. The metallic caps 2 are cup-shaped and areseverally provided with a central opening 7.

As illustrated in Figs. 2 and 3, the upper edge or rim 8 of the tubular member 1 is provided with opposed spaced notches in `which projections 9 and 10, formed on a tively as the projections 9 and 10 formed on the washer 1l. The washer 11', shown enlarged in l, is preferably provided with a rectangularI body portion upon which the projecting portions. 9 and 10 are formed YThe projections 12 and 13 of the terminal member `3 are located at points corresponding `to theprojections l0 and 9 formed on the washeill. When my electricalfuse is assembled, as shown in Fig. 3, the corresponding projections of the terminal meni- `ber '3 Aand of the washer 11 are superposed and received in the notches cut in the upper edge or rim 9 ot the member 1,

YThe fusible element 14, made of any suitable material such as `a Zinc alloy, is provided with restricted portions 15 and 16, the portion `15 being intermediate the portions 16. TheV end portions of the fusible. element 14C are provided with longitudinally extend-v ing slots 17. ln assembling the renewableV ing knife-blade portion The two ends of .Vall

electric fuse of my invention, the fusible element 141 has one only of its ends bent o'fer as shown at 18 in Fig. 5. The projection 10 formed on the meta lic Washer lV is extended through the slot'lZthe Wash' 1 1 engaging the bent-over end 18 of the i sible elementJ on its under side. In this position the bentover end 18 extends longitudinally of the Washer 11 and engagesit on its outer surface. The bent-over end 18 may be provided With an outer contour which coincides generally with that of the Washer 11 excepting for the projections 9 and 10 formed on the Washer.

The slot 17 provided in the bent-Over end 18 extends beyond a threaded opening 19 formed in the Washer 11. The Washer 11 engages the fusible linlr element 1- as explained above and is then positioned relative to the insulating easing 1 so that the fusible element 1li. extends therethrough. rllhe Washer 11 is properly positioned by reason of the projections and 10 being received in the proper notches cut in the riin 8 of the insulating casing 1. The metallic cap Q in which the terminal member Z3 is received .is then screwed upon the end of the casing` 1 in such fashion that the bent-over end 18 of the fusible linl; 141- is held intermediate the underside of the flat portion (i of the terminal member 3 and the upper face of the Washer 11.

`Moreover, the projections 12 and 18 formed on the terminal member 3 are positioned so as to be received in the proper notches cut in the rim 8 of the casing 1. firmly screwingthe cap 2 to the threaded end of the insulatingcasing` 1, the bent-over end 18 of the fusible element may be retained in close contact with both the terininal `ineinbers and the washer 11. However, to ensure permanent and goed electrical contact under all conditions a screw 2O may be provided which extends through the flat portion 4 of the terminal member 3, the slot 17 formed in the bent-over end 18 of the fusible element 14 and the threaded opening 19 formed in the Washer 11` By tightening the screw 2O it will be observed that the three electrical 'conducting members of the fuse, namely, theterininal member 3, the fusible clement 14C and the metallic washer 11 are pern'ianently maintained in close electrical Contact reven lthough the cap member f2 becomes loosened upon the shell or casing 1. The screw 2O serves to retain this electrical connection intact. lt is also to be observed that the `screw 2O Wil tend to retain the knife blade terminal 5 in a fixed position upon the insulating shell 1 When the electric fuse is being inserted in the fuse clips. 1t is known that when inserting ordinary electric fuses in the retaining` fuse clips the pressure exerted by the clips tends to displace the knife blade terminal from the associated shell or casing. permanently securing together the Washer ii, the fusible linlr 1a'- and the 'terminal member 8 by means of the screw 20, the i" members of the fuse will not ten i to become loosened.

After the fuse has been assembled shown in Uig. 2, corresponding elemente may be placed in pos' fon at the other end of the casu g l. This is effect-ed by bendii V over the stL ght end of th'. "fusible linlr as shown by the bent-over The washer 11 and the terminal me similar to those at the upper l o i the fuse, may then be placed in. position with 'the bentover end 21 of the fusible element .11- between si them. A c and a screw El() will then be threaded positioi'i tl both or the electric i ise ivill .te ii entieal.

The modified form of ny electric similar to the elect ln this instance, hoive'if'er, ture in the forni of a ci connnon forni of consti 'lhe fusible element in illustrated in liirg. ant. the of this L" V)le e. ement may washers 2o that e similar to 1 The cap 22, i. this instanc With an integrally formeu central openingr -irough nl may be inserted. The

stance, is centrally positu 22 and is threaded into l formed in the Washer 23. lt will be noted that the bent-over nds ci the fusible element are placed intermediate the washer 23 and the flat -face formed on the metallic cap member E22. rThe screw 20 Which projects through these three'metL ic elements ensures a Agoed electrical contact at all times.

VJ hen refilling the fuses herein described it is necessary only to remove the caps 2 and 22 as Well as the screws 20. This permits the fusible linl; 14 to be readily replaced by a nen7 one. 'it Will be noted that the permanent members of my renewable fuse are few in number and that their combination pro vides a very rigid structure. Moreover, the screw 2O ensures goed electrical contact at all times between the parts designed to carry the electric current. The insulating casing 1 is adapted for continuous use and does not deteriorate under repeated ruptures of the f sible link 1li contained therein.

lVhile 1 have described in detail several embodiments of my invention it is to be understood that I desire only such limitations to be imposed thereon as are set forth in the appended claims.

Having thus described my invention, what 1 claim te new and desire to secure by Letters Patent is:

1. An enclosed 'renewable fuse comprising a tubular container, a knife blade terminal member having a flat portion covering the end of said tubular container, awasher beneath said Hat portion, said lat portion and said washer being provided with superposed lugs engaging saidy container, a fuse link having a bent-over end retained between said flat portion and said washer,'and means for retaining said lat portion on said container.

2. An enclosed renewableiiuse comprising a tubular container, a knife blade terminal member having a fiat portion covering the end of said tubular container, a washer be neath said fiatportion, a fuse link having a bent-over end retained between said fiat portion and said washer, a ferrule independent of said terminal member for retaining said flat portion on said container, and retaining means extending from said flat `portion through said fuse link and into said washer.

8. An inclosed renewable fuse comprising a tubular container, a knife blade terminal member having a at portion covering the end of said tubular container, a washer beneath said flat portion, said flat portion and said washer being provided with superposed lugs engaging said container, a fuse link having a bent-over end retained between said ilat portion and said washer, said bentover end being provided with an opening through which the lug on said washer passes, and means for retaining said fiat portion on said container.

4. An enclosed renewable fuse comprising a tubular container, an end cap therefor, a

washer contained in said end cap, said washer having a lug engaging the'end of said container, and a fuse link in said container havingv a bent-overV end positioned over said washer in said-end cap, said bent-over end being provided with an elongated opening through which said lug extends.

5; An enclosed renewable fuse comprising a tubular container, end cap means therefor, a washer contained in said end cap, said washer having a lug engaging the end of said container, a fuse link in said container having a bent-over end positioned over said washer in said end cap means, and retaining means extending from said end cap means through said bent-over end and into said a fuse link having an end bent over a face of said washer member, and means for retaining said end upon the face of said washer, said end being formed with an elongated slot through which said lug and said means pass.

In witness whereof, I have hereunto subscribed my name.

, ROY G. SANDS.

lVitnesses GEO. W. HANSEN,- A. AnNoLn BRAND. 

